Billing issues and terrible service

I upgraded to a new Vodacom contract in January. After I upgraded I asked the consultant how long I was going to have to pay for my old handset whereby the consultant informed me it would be a once off with the new contract and that this would be effective in February's installment. I then phoned Vodacom in March after my monthly instalment did not decrease as informed by the consultant. I spoke to a consultant which then said the system was offline and that she would phone me back. It has been a month now and I still did not receive any feedback from Vodacom. I am currently paying for two handsets and my contract fee has not decreased as I was informed by the consultant. I do not see why I have to keep on paying R785.98 for a contract which was supposed to be R665.57 per month. Vodacom has not contacted me nor informed me why I have to continue paying for two handsets after being informed that it would be a once off.

Furthermore I received 10 gigs of data when upgrading which Vodacom decided the would just take after a month. I will be looking at moving all my contracts with Vodacom as this is not the first time I have had issues.